Question

3 erasers and 2 pencils cost $0.80; 4 erasers and 5 pencils cost $1.65. What is the price of one eraser? what is the price of one pencil?

Answer 1

Given - Cost of 3 erasers and 2 pencils : $0.80

Cost of 4 erasers and 5 pencils : $1.65.

Find - Price of one erase and one pencil.

Solution - Let us assume cost of one eraser to be x and cost one pencil to be y.

Representing given information in equation form -

3x + 2y = 0.80

4x + 5y = 1.65

Equalising the value of X, by multiplying first equation with 4 and second equation with 3.

12x + 8y = 3.20

12x + 15y = 4.95

Subtracting the equation we get -

-7y = -1.75

y = 0.25

Therefore, cost of one pencil is $0.25.

Calculating cost of one eraser-

3x + 0.5 = 0.80

3x = 0.3

X = 0.1

Hence, cost of one eraser is $0.1